Method and apparatus for manufacturing tin openers



June 4, 1929. BAUER 1,715,812

METHOD AND APPARATUS FOR MANUFACTURING TIN OIENERS Filed May 10, 192'! Fatented June 4, 1929.

UNITED STATES 1,715,812 PATENT OFFICE.

FRIEDRICH BAUER, OF IFORZHEII, GERMANY.

mnon AND APPARATUS FOR MANUFACTURING TIN OPENERS.

Application filed Kay 10, 1927, Serial No. 190,340, and in Germany Kay 11, 1926. v I

This invention relates to" a method and apparatus for manufacturing openers for sheetmetal, specially shoe-cream boxes, said openers comprising a; hollow rivet turned inside out like a sack, and for rotatably and tightly fixing the same on the flange of the box.

Box-openers of various shapes have become known which form a two-armed lever or eccentric riveted oscillatably on the flange of the box, so that, when being rotated, it grips from below under the edge of the lid of the box and raises the same. type are manufactured in such a manner that a sheet-metal blank corresponding in size to an opener is cut out, these blanks being success'ively shaped in different presses and punching machines. Owing to the irregular and unwieldy shape of the sheet-metal blanks they cannot be automatically conveyed to the working points of the diflerent machines by means of a channeled magazine but must be placed singly by hand onto the die.

The box-opener has been fixed hitherto in such a manner'that the stud of the opener turned inside out like a rivet is inserted by hand into a hole, made in the flange of the box by a separate punching-machine, whereupon the rivet head is swaged in another press, the opener being carefully held in its position on the box.

The improved method presents very great advantages in comparison with the common- 1y used methods,

It consists in that the indentin of the opener, turning inside out of the stu cutting out and erecting of the handles, and stamping of the blank are effected by means of tools carried by one and the same tool-head and from a vcontinuously conveyed sheet-metal strip, whereupon the stamping plunger pushes the finished opener, the handles of which are still held between the plunger-shaft and the wall of the die-hole, or by the own resiliency of the handles on the wall of the die hole so that the openers-cannot accidentally drop through the die-hole towards the perforated flange of the box, so that the rivetstud is inserted and pressed fiat upon an anvil 'moved towards the inner side of the flange.-

. While the commonly used method requires 15 men and 15 machines for working for in-- stance 20,000boxes per day, one single ma chine requirinfigfor attendance only one single person can nish, according to the new method, 23,000 box-openers per day and fix the same on the boxes.

Openers. of this It is possible to increase the output, with the aid of skilled workmen and by increasing tlhe spefi of the machine, to 30,000 boxes per A formof construction of the machine for carrying out the new method is diagrammatically shown, by way of example, in the accompanying drawing in which Fig. 1 shows in end elevation and Fig. 2 in side elevation partly in a vertical section on line 2-2of Fig. 1, the improved machine.

Fig. 3 shows in plan view a portion of the sheet-metal strip, which has been worked in the machine.

\ Fig. 4: shows the box in section on line 4, 4 of Fig. 5.

Fig. 5 is a plan view of Fig. 4.

The working method is carried out in the followin manner The co s a of the revolving disk a, which executes an intermittent automatic revolvingmovement in the direcetion of the arrow line D, are filled from a magazine 0 with parts 6 of boxes said parts rolling from said magazine in the direction of the arrow-line C. These parts of the boxes are held, during the intermittent rotating of the cells a, by means of holding arms 6 controlled by a pressure in opposition to the action of the spring (1 at these points during the time when the revolving disk a. is stopped, this interval taking place between twoconveying movements, so-

that the parts I) of the bdxes roll into the cells a and drop out of the same without'anyimpediment.

The part b which has rolled into'a c ll will then be conveyed by an intermittent part rotation of the revolving disk (1 to the first workin point and subsequently to the sec-;

ond wor mg point: Arrived atthe firstworking point the shiftable die 7 penetrates into the box part whereupon the'punch g advances in the direction of the arrow line E ...-radially from the outer side towards the flange-of the box to punch a hole k. Prior to the beginning of the next following conveying movement thedie f withdraws frbm inside the box.

A strip k of sheet metal is intermittently moved over a die plate t at right angles to the plane in which the revolving disk is sit uated, i. e. in the direction of the arrow line A (Fig. 2), said strip is being worked upon at several points by pressing and punching tools m, n, p, g, s so that continuously perfectly finished box opener-st" are produced. The punches m and n serve'i'or producing the preliminary indentations which, at the two following working points, are deepened by means of the punches p and g to form the I hollow stud 1 which is not perforated. At

the last working point the cutting punch s stamps the box opener i out of the strip is of sheet metal and pushes it downward so that the handles of the box opener z" are held between the shaft of the punch a and the wall of the die-hole, the opener being thus prevented from dropping out. Even when. the handles have another shape as shown they can be shaped so that they securely hold the opener in the die holeuby their own resiliency.

The hole 72. in the part Z) of the box stands, after the conveying from the first working point to the second working point, accurately underneath the stud r of the box opener 2' which has been pushed out of the lower end of the cutting hole of the die 25. At the second working point the anvil u, shittable in the direction of thearrow line B, is advanced into the part b of the box, whereupon the rivet stud r penetrates into the hole k of the box flange. By a strong pressurehexerted by the riveting punch 8 made in one part with the stamping punch s, the rivet head 0 is pressed, which closes the hole it, whereupon the anvil u withdraws from the box so that this box can travel towards the point of delivering.

At every part rotation of the revolving disk at an opener 2' is automatically fitted into a box 6 with the aid of the machine. The workman who attends the machine has nothing to do but to continuously fill the magazine 0 with parts I; of the boxes.

The tools m, n, 50, g, s are carried all in one tool head which is operated, in the well known manner, from a crank shaft or from.

an eccentric shaft. From this main shaft the movements of all the other tools 7, g, a, o oi the revolving disk a and of the strip 01 sheet metal are controlled with the aid of commonly used means as cam disks, levers, connecting rods and rollers.

In the drawing the box part b is shown as bottom part. The method and apparatus according to the invention may however be used also for fixing the opener on the lid of the box.

If, instead of a rivet turned inside out and havin a bottom, a stud with continuous bore or a anged hole has to be produced on the, box opener 2' before this opener is inserted,

' -With the aid of the inserting tool 8, into the hole h of the flange of the box, the opener 2' has to be fixed in the part Z) of the box by means of a wire rivet to tightly pack the hole and to securely fixthe opener. The working phases necessary for this purpose may be carried out on two other working points of the machine. At the first of these additional working points the rivet, cut ofi the wire, is inserted into the stud hole of the opener, and at the second working point this rivet is swaged:

1 claim l. A method of fitting tin openers on the edge of tins, consisting in consecutively cor;- veying tin openers, still connected with the sheet metal strip from which they have been stamped and having each an extension designed to serve as rivet, above holes in the side wall of the lower tin part, in conveying said lower tin part so that the corresponding hole is standing accurately under a rivet, and in ramming the rivets successively into the corresponding holes.

2. An apparatus for fixing tin openers in the flange of box parts, comprising in combination a die plate having a group of cavities and a die-hole, a revolving disk having cells holding each one box part said disc revolving in a plane at right angle to said die plate and conveying said box parts to under said thehole, and a tool head carrying a pressing punch and a cutting punch above said rotary disc said cutting punch pushing a finished opener from said die plate through said diehole against the flange of said box part to rivet the opener in said flange.

3. A machine for fixing tin openers in the flanges of box-parts, comprising in combina tion a revolving disk comprising several cells, a channelled magazine for supplying at each part revolution of said revolving disk one bottom part of a box to one of said cells, a the plate comprising a number of working points consisting each of a die the end die extending from the upper to the lower surface of said die-plate, a tool holder above said dieplate and having as many tools as there are dies, an anvil underneath said die-plate, and

mieans for intermittently operating said tool head and said anvil so that when the opener which has been successively prepared in the difierent dies is inserted by the extreme tool into the perforated flange of a bottom part of a box said anvil is advanced into said bottom part so that the stud of said opener is flattened.

4. Amachine as specified in claim 3, comprising in combination with the tool head and with the revolving disk stepwise rotated, a shiftable die adapted to engage with the box part, and a punch in said tool head for punching a hole into the flange of said box part in cooperation. with said shiftable die.

5. In a machine, as specified in claim 3, thefinishing tool consisting of a punch for pushing the opener through the die into the hole in the flange of the bottom part of a box, and of a rivet punch for flattening the rivet stud of said opener when it has been inserted into the hole of the-box flange.

6. An apparatus for fixing tin openers in the flanges of box parts, comprising in combination with the die-plate having a grou of dies, a holding arm oscillatably mounted on each'cell, a sliding finger at the front end of each holding arm, a cam disk at the point at which the bottom parts of the boxes enter into a cell, a cam disk at the point at which said bottom parts are discharged from the cells said cam disks serving to lift said sliding fingers and through the same said holdingarms to release the corresponding bottom part of a box, and a pressure spring acting uponsaid holding arms so that they normally hold the correspondingbottom part of a box in the corresponding cell during the treatment, a tool head above said die-plate and tools in said tool head one for each die, a revolving disk for intermittently conveying at each part revolution to underneath the extreme die one bottom part of a box.

In testimony whereof I aflix mysignature.

FRIEDRICH BAUER. 

